Uberti Cattleman .44 w/ No Half-Cock

You sure it’s supposed to have one? Lots of Rugers don’t, for example.

Does the cylinder free spin with hammer down and the loading gate open? That click your hearing is the bolt dropping most likely. If the cylinder spins free only when the hammer is pulled to what would be a half cock notch something is broken internally, most likely the half cock notch on the hammer.

If you turn the revolver upside down and cock it slowly you should be able to watch the bolt retract and pop back up, see if this corresponds with the Audible click sound.

I would take the hammer and trigger out to see if it the hammer has a busted half cock notch or if the tip of the trigger is busted.

I doubt anything made by Iver Johnson let alone in 1975 would be anything else but a Colt clone using an old Colt action. That means no transfer bars, no rebounding hammers, no free spinning cylinder by merely opening the loading gate. It's just an old fashioned 5 loaded hammer down on empty chamber Colt type action that IS SUPPOSED TO BE IN HALF COCK WHEN LOADING.

I am not sure if finding a new hammer or trigger for this is going to be patient search for used or new old stock part/parts. I don't know if the newer old style hammer or trigger of the fairly recently discontinued (I think it's dc ed) old style action cattleman is going to fit. The 1970's models are made before they were using CNC machines. Maybe someone who knows more can chime in.

If the half cock notch on the hammer is broken, a good smith can re-cut the notch without having to replace the hammer.

My thoughts exactly, still have not determined this to be the problem. It's gonna require being taken apart to really know what's going on.

Maybe something like this. I don't know if Uberti parts or guns finished by Iver Johnson during the 1970s. are an exact match with other Uberti Cattleman parts..

https://www.brownells.se/WebRoot/MediaDefinition/userdocs/schematics/u-1873_CattlemanSA.gif

http://www.ubertireplicas.com/wp-content/uploads/2014/09/0358_1to182.jpg

The quick way to tell the Colt clone from the modern transfer bar one is does the hammer have a point or is it flat.

Some info about Uberti Cattleman .44 mag imports to Iver Johnson

https://www.thehighroad.org/index.php?threads/uberti-cattleman-44-magnum.873888/

https://fasrvector725.weebly.com/blog/iver-johnson-cattleman

Opinions on Iver Johnson Cattleman revolvers vary. Deformation of firing pin holes in .44 magnums after being fed a steady diet of magnum loads is one complaint. .44 special loads from mild to hot may be a viable solution to this?

If you are fortunate the edge of the half cock notch on the hammer may be bent over blocking the trigger from entering. That can probably be fixed. TAKE IT APART AND LOOK if it's within your capabilities.

I read that parts were imported by Uberti to Iver Johnson between 1974 and 1978 with final fit and finishing done by Iver Johnson. I am not sure of that and information during my web search is scarce. Whatever the case it's not a CNC gun and hand fitting may be necessary even with original parts..

This site below (Numrich aka gunpartscorp.com) has some (4 pages) old new stock or used Iver Johnson Cattleman parts.

Hammer (get Centerfire Hammer) is in stock here at $45.00 (probably)
https://www.gunpartscorp.com/gun-manufacturer/iver-johnson/revolvers-ij/new-cattleman-mag?page=3

Numrich takes forever and it may not be in stock despite being listed as so. I don't know

trigger is listed as out of stock..

It actually may be an easy fix making most of this moot.

You can choose to dispense with the hassle and send it to a gunsmith who knows how to work with Colt type single actions, deliver it to them, pay and wait for the work to be done.

If the work can be done with a $10.00 (maybe less) mini file set from Home Depot it may make the other suggestion moot. Don't touch the trigger or full cock notch with a file though since the hardened surfaces must be left intact.

A worthwhile mention: getting the geometry of the edge (should be somewhat sharp and ramped) near the half cock notch right can be tricky. Failure to do so can result in the hammers outer edge near the half cock notch slamming down on the trigger tip the moment the trigger tip is pulled out of the full cock notch way before you can pull the trigger all the way back out of the way. If the actual inside of the notch is wrong (not a wide enough opening) then your trigger can get stuck (locked in) in the half cock notch locking up the action.

Look for file marks, the notch may have been removed intentionally.
Elmer Keith discussed removing safety and half cock notches to protect the sear nose of the trigger.
'Sixguns', chapter XV, page 218 in my edition.